{	Problem: http://codeforces.ru/problemset/problem/59/A
	Verdict: Accepted

}
var s:string; i,a,b:longint;
function low(s:string):string;
var i:integer;
begin
for i:=1 to length(S) do if s[i] in ['A'..'Z'] then s[i]:=chr(ord(s[i])+32);
result:=s;
end;
function up(s:string):string;
var i:integer;
begin
for i:=1 to length(S) do if not(s[i] in ['A'..'Z']) then s[i]:=chr(ord(s[i])-32);
result:=s;
end;
begin
readln(s);
a:=0;
b:=0;
for i:=1 to length(s) do if s[i] in ['A'..'Z'] then inc(a) else inc(b);
if a>b then writeln(up(s)) else writeln(low(s));
readln;
end.